System and method for re-routing failed video calls

ABSTRACT

A system and method for re-routing a failed video call schedules one or more reserve video devices for use in the event of failure of the video devices selected to support a video call. Upon detection of a failure of a video device, the video network platform re-establishes the video call by using the reserve video devices to replace the failed video device, thus avoiding the waste of video network resources and delays in the completion of a video call. More efficient use of reserve video devices is obtained by pooling the reserve video devices with a reserve video network that supports plural primary video networks.

TECHNICAL FIELD OF THE INVENTION

This invention relates generally to video communication networks, andmore specifically relates to a system and method for re-routing a failedvideo call.

BACKGROUND OF THE INVENTION

Video calls provide an excellent forum for meetings between participantswho cannot travel to meet in one location. By capturing both audio andvisual presentations of participants, video calls are often the nextbest thing to a personal meeting in one location. Advances in computerand networking technology have greatly reduced the expense of conductingvideo calls and maintaining a video network. Thus, complex video callsbetween a large number of participants have grown more common as amedium for conducting large scale business meetings.

Although video calls are an excellent alternative to in-person meetings,the scheduling, configuration and set-up of a video call is often acomplex task that becomes increasingly complex as the number ofparticipants in the video call increases. For instance, video callsinvolving three or more endpoints typically must be routed through amulti call unit (MCU) or several MCUs with each endpoint routed throughan MCU port in order to coordinate presentation of the video call. Asanother example, if video endpoints use different protocols, then agateway device is generally needed to establish and maintaincommunications between the endpoints. In addition, conventional videonetworks which involved hardware MCU and gateway assets areincorporating video over internet protocol technology so that MCU andgateway functions are also performed by servers routing TCP/IP packets.

Once a configuration for a complex video call between a large number ofvideo endpoints is established, the hardware and software assets forsupporting the video call typically are scheduled for the video call inadvance and set aside so that others will not use the assets. Forinstance, technical staff that oversees the assets and the networkbandwidth will make the video devices inaccessible to unauthorized usersand will set aside bandwidth to support the video call, either through alocal video network or through third party networks such as the PublicSwitched Telephone Network (PSTN), private networks or the Internet.This process of scheduling video devices tends to decrease theusefulness of video call networks since other ad hoc video meetings aremore difficult to establish if assets are tied-up by scheduling inadvance.

The complexity associated with configuring and setting up a video callhave led to some hesitation by users for the wide spread adoption ofvideo communications. Another related difficulty that has slowed theacceptance of video calls is that video devices are sometimesunreliable. The more complex the proposed video call, the more likelythat a failure of a video device or the video network will disrupt thevideo call. For instance, if a video call is configured through threeMCU devices, then the failure of a single MCU device may prevent thecompletion of the video call and the goal of the participants of thevideo call. As another example, failure of portions of a video networkmay result in reduction of available bandwidth so that the quality of avideo conference is dramatically affected to the point of degradation ofthe purpose of the video call. In such instances, the participants ofthe video call generally must reschedule the call or find availableassets to support reconfiguration of the call. However, even if assetsare available to reconfigure the video call, a significant delay in thevideo call is typically introduced as the call is reestablished, oftendegrading the purpose of the call and the advantage of a video call overa personal meeting of regular audio telephone conference call.

SUMMARY OF THE INVENTION

Therefore a need has arisen for a system and method which re-routes avideo call to overcome a failure in the video network that degrades thevideo call.

A further need has arisen for a system and method which schedulesreserve video network assets to avoid degradation of a video call if afailure of the video network occurs during the video call.

In accordance with the present invention, a system and method areprovided which substantially reduces the problems and disadvantages ofconfiguring and scheduling video devices for a video call across a videonetwork. Reserve video devices are scheduled for use in the event offailure of primary video devices used in a video call configuration.Upon detection of failure of a primary video device, the video call isre-routed from the failed video device through the reserve video device.In this manner, a pool of resources are actively managed and scheduledto more effectively maintain video network communications.

More specifically, a video network platform interfaces with a videonetwork to monitor, schedule and optimize video network performance. Aschedule configuration engine configures a video call with selectedvideo devices and schedules the video devices for the call at thedesired time. The schedule configuration engine also schedules one ormore reserve video devices for use in the event of failure of one ormore of the selected video devices. A video device controller initiatesa video call as configured by the schedule configuration engine andmonitors the call to ensure that video devices work properly. Upondetection of a failure of a video device, the video device controllerre-routes the video call from the failed video device and through thereserve video device.

In one embodiment, a scheduling platform associated with a pool ofreserve resources provides improved flexibility for scheduling reservevideo devices. For instance, a scheduling platform associated with thirdparty video devices acts as an external bridging system to providereserve video devices for a configured video call. A video devicecontroller of the scheduling platform negotiates with the video devicecontroller of the video network platform to schedule video devices asreserve video devices and to activate those reserve video devices uponfailure of a primary video device. For example, a video network platformhaving two scheduled video calls that each use an MCU may schedule areserve MCU in case either one of the two primary MCUs fail. As afurther example, the scheduling platform may divide the allocation of areserve MCU over a given time period between several different MCUs sothat maintaining a reserve does not unnecessarily tie up availableassets. If a failure occurs, the scheduled reserve video device is madeavailable to the video network platform and is used to maintain thevideo call.

In one embodiment, video devices are scheduled to support video callsand unscheduled video devices are placed in a reserve pool accessed bythe schedule configuration engine. The reserve pool of video devices isused to provide primary video devices for newly-scheduled video callsand also provide reserve video devices for scheduled video calls byestablishing alternative schedules that account for primary video devicefailures. The schedule configuration engine determines if the reservepool is adequate to ensure a desired level of video call reliability,such as by modeling reliability. If a desired degree of reliabilityrequires a larger pool of reserve video devices, the scheduleconfiguration engine cooperates with the video device controller tonegotiate for additional reserve video devices, such as from externalbridging companies. The pool of reserve video devices is dynamic innature so that as reserve devices are called upon, the reserve pool isre-allocated and added to as necessary to maintain a desired level ofreliability.

The present invention provides a number of important technicaladvantages. One important technical advantage is that the reliability ofvideo of calls, especially complex video calls involving greater numbersof video devices, is improved by scheduling reserve video devices toreplace video devices that fail. The video network platformautomatically maintains or re-establishes a configured video call in theevent of a video device failure without wasting time searching foravailable reserve devices. The video device controller automaticallymaintains an adequate reserve of video devices for configured videocalls so that, upon detection of a video device failure, the disruptionof the established video calls is minimized.

Another important technical advantage of the present invention is thatvideo device resources are more efficiently used. For instance, reservevideo devices scheduled in case of failure reduce the risk that aconfigured video call will be wasted if a video device failure occurs.Video calls may be prioritized to ensure that the most important videocalls are completed and the scheduling of reserve video devices may takeinto consideration probabilities of failure for primary video devices tohelp ensure that adequate reserve video devices are available. Automaticnegotiations with third party bridging services maintain an adequatereserve of video devices to avoid extended disruptions of video callservice.

Another important technical advantage of the present invention is thatan administrator of a video network may schedule reserve video devicesto accommodate potential failures in the video network. The availabilityof third party video devices as reserves for a video call allow theadministrator to fully utilize video devices associated with theadministrator's video network with reduced risk that a failure willdisrupt scheduled video calls. This helps to fully utilize availablevideo device resources and reduces wasted assets and the costs ofsecuring outside vendor systems and services.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present embodiments and advantagesthereof may be acquired by referring to the following description takenin conjunction with the accompanying drawings, in which like referencenumbers indicate like features, and wherein:

FIG. 1 depicts a block diagram of a video network operable to re-routefailed video calls; and

FIG. 2 depicts a block diagram of a video network platform andscheduling platform for coordinating reserve video devices.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention are illustrated in theFIGURES, like numerals being used to refer to like and correspondingparts of the various drawings.

Scheduling reserve video devices to back-up video calls in case offailure of primary video devices helps to reduce video call failure,especially with complex video calls that span many devices. However,maintaining video devices on reserve can result in valuable video deviceassets sitting idle when no failures occur. A schedule configurationengine according to the present invention reduces the expense ofmaintaining reserve video devices and increases video call reliabilityby scheduling reserve devices based on projected failures and relying onthird party devices outside of the video network to act as the reservedevices.

Referring now to FIG. 1, a block diagram depicts a video network havingplural video devices interfaced to support video calls. A video networkplatform 10 controls video endpoints 12, gateways 14 and MCUs 16deployed within a video network 20A. A video network 20B interfaces withnetwork 20A, such as through a telecommunications network 20, like thepublic switched telephone network or the internet. A scheduling platform18 controls gateways 14 and MCUs 16 in a video network 20C thatinterfaces with video networks 20A and 20B through network 20.

Video network platform 10 configures, schedules and controls video callswithin its local video network 20A. For instance, video network platform10 may configure a video call between endpoints A1, A2 and A3 using MCUA and gateway A without accessing other devices through network 20.Video network platform 10 may establish a video call using video devicesfrom video network 20B and video network 20C by communicating with thosevideo devices through network 20. As an example, video network platform10 may establish a video call between endpoints A1, A2, B1 and B2supported with one of MCUs A, B, C1 or C2 by sending a command to therespective MCU to initiate a video call to each end point. However,failure of the MCU will lead to failure of the video call.

In order to reduce the risk that a failure of a video device will leadto failure of a video call, video network platform 10 configures a videocall with selected video devices and also schedules one or more reservevideo devices for use in the event of failure of one or more of theselected video devices. For example, video network platform 10configures, schedules and initiates a video call between endpoints A1,A2 and B1 through MCU A and reserves MCU C1 in the case of failure ofMCU A. If, during the video call, MCU A fails, then video networkplatform 10 re-initiates the video call using MCU C1. Depending upon thetype of video network, re-initiation of the video call might involvere-dialing the endpoints through the reserve MCU or re-routing TCP/IPpackets through a server performing MCU functionality.

Referring now to FIG. 2, the block diagram depicts that video networkplatform 10 and scheduling platform 18 interface through network 20 tocoordinate the scheduling of primary and reserve video devices. A videodevice controller 24 supports control of local video devices by videonetwork platform 10 and scheduling platform 18, such as initiating orterminating video calls at MCU or gateway devices. A scheduleconfiguration engine 26 schedules video devices for video callsinitiated or controlled by video network platform 10. A schedule 28tracks the scheduled video calls for each video device, including itsprimary and secondary schedules. A video device scheduler 30 tracks theschedule for video devices associated with scheduling platform 18, suchas MCUs and gateways of video network 20C. A scheduling platformschedule 32 tracks the video devices associated with video network 20C,including their primary and secondary scheduling activities. A devicedatabase 22 stores information for the video devices such as addressinformation, functionality information, and reliability information.

In operation, a user initiates configuration of a video call throughselection of endpoints. Schedule configuration engine 26 schedulesprimary video devices to support the video call, including the MCU andgateway devices, and also schedules reserve video devices to replaceprimary devices in the event of failure. Reserve devices may be selectedfrom video network 20A associated with video network platform 10 orselected from video network 20C through coordination of video devicescheduler 30 and schedule configuration engine 26 communicating throughvideo device controllers 24. Should a video device fail, video devicecontroller 24 detects the failure and activates the scheduled reservedevice to replace the failed primary video device. Scheduleconfiguration engine 26 schedules reserve devices based in part on thehistorical reliability of scheduled video devices stored in video devicelibrary 22. Thus, a predetermined video call reliability is obtainableby scheduling a reserve video devices as a pool for multiple primaryvideo devices and multiple video calls. Should a reserve video device becalled upon to replace a failed video device, video device scheduler 30in coordination with schedule configuration engine 26 re-assigns theremaining primary video devices to a different reserve device.

In one embodiment, schedule configuration engine 26 provides apredetermined level of reliability while supporting full utilization ofnetwork 20A video devices by using a third party network 20C to providereserve video devices. The use of a third party pool of reserve videodevices allows more efficient use of video devices of video network 20Aby spreading the risk of video device failure over a greater number ofvideo networks that rely on the reserve pool of video devices. Thescheduling is coordinated between schedule configuration engine 26 andvideo device scheduler 30 through video device controllers 24. If afailure is detected, the video call is re-routed through the third partyreserve video device.

One advantage of the present invention is that the use of a third partypool of reserve video devices allows a video network to more efficientlyuse video devices in a primary role by relying on the third party poolto provide a predetermined reliability by assigning an appropriatequantity of reserve video devices. The cost of maintaining the pool ofreserve video devices is reduced since that cost may be spread over anumber of video networks and spanning a number of video calls. Forinstance, one or more primary video networks may schedule fractionalreserve video devices from a pool, rather than whole video devices, sothat the combined scheduled reserve devices are more efficientlyallocated as whole devices backing-up several primary video networks. Inother words, one reserve device may back-up several primary deviceswhere the risk of failure is acceptably low. As reserve devices arecalled upon to replace failed primary devices, the quantity of reservedevices needed to obtain a desired degree of reliability may bere-calculated by video device scheduler 30 and the pool increased ordecreased as needed. Moreover, the degree of reliability may becontrolled so that video calls having a greater priority are handledwith a greater reserve priority, thus ensuring the highest degree ofreliability for those video calls.

Although the present invention has been described in detail, it shouldbe understood that various changes, substitutions and alterations can bemade hereto without departing from the spirit and scope of the inventionas defined by the appending claims.

1. A system for re-establishing failed video calls through a videonetwork having plural video devices, the system comprising: a routingmodule operable to schedule video devices as primary video devices thatsupport a video call and reserve video devices that replace failedprimary devices; and a a diagnostic capability unit interfaced with therouting module and the video devices, the diagnostic capability unitoperable to detect a primary video device failure and to activate areserve video device scheduled to replace the failed primary videodevice.
 2. The system of claim 11 further comprising: a reserve videonetwork interfaced with the plural video devices, the reserve videonetwork having plural video devices available for scheduling for use bythe diagnostic capability unit; and a reserve diagnostic capability unitinterfaced with the reserve video network and communicating with thediagnostic capability unit to negotiate control of reserve video networkdevices by the diagnostic capability unit.
 3. The system of claim 2,wherein the routing module is further operable to determine a quantityof reserve video devices that provide a predetermined reliability levelfor the scheduled video calls based in part on the probability offailure of the primary video devices.
 4. The system of claim 3, whereinthe routing module is operable to reserve video devices from the reservevideo network if the plural video network devices are inadequate toachieve the desired reliability level.
 5. The system of claim 1, whereinthe video devices comprise an MCU.
 6. The system of claim 1, wherein thevideo devices comprise a gateway.
 7. The system of claim 1, wherein thevideo devices comprise network bandwidth for transferring video callinformation.
 8. A method for re-establishing a failed video call over avideo network having plural video devices, the method comprising:configuring a video call with selected video devices; scheduling one ormore reserve video devices for use in the event of failure of one ormore of the selected video devices; detecting failure of one of theselected video devices; and re-establishing the video call from thefailed video device through a reserve video device.
 9. The method ofclaim 8 further comprising: scheduling plural video calls; determining aquantity of reserve video devices to achieve a predetermined level ofreliability for the scheduled plural video calls; and scheduling thedetermined quantity of reserve video devices.
 10. The method of claim 9further comprising: determining that an inadequate quantity of reservevideo devices are scheduled to achieve the predetermined level ofreliability; and negotiating additional reserve video devices from areserve network.
 11. The method of claim 8 further comprising: detectinga video call failure associated with a video device failure; andre-establishing the video call with a reserve video device to replacethe video device failure.
 12. The method of claim 11 further comprising:re-determining the quantity of reserve video devices to achieve thepredetermined level of reliability for the scheduled plural video callsin light of the video device failure; and scheduling the re-determinedquantity of reserve video devices.
 13. The method of claim 12 furthercomprising: determining that an inadequate quantity of reserve videodevices are scheduled to achieve the predetermined level of reliability;and negotiating additional reserve video devices from a reserve network.14. A method for scheduling a video call, the method comprising:determining a video call configuration for the video call, the videocall configuration having plural video devices; identifying one or morevideo devices as susceptible to failure; identifying one or more videodevices as reserve video devices to support the video call in the caseof failure of the susceptible video device; and scheduling the videodevices and the reserve video device for the video call.
 15. The methodof claim 14 further comprising: using the reserve video device tosupport a second video call during the scheduled video call; andscheduling a second reserve video device in the place of the reservevideo device.
 16. The method of claim 14 wherein the scheduled videocall is for predetermined time period, the method further comprising:scheduling a first reserve video device for a first portion of thepredetermined time period; and scheduling a second reserve video devicefor a second portion of the predetermined time period.
 17. The method ofclaim 16 wherein the reserve video device is associated with a reservevideo network.
 18. The system of claim 1, wherein a failure is a networkinterruption.
 19. The system of claim 1, wherein the routing module isfurther operable to enable end-to-end call routing.
 20. The method ofclaim 8, wherein a failure is a network interruption.
 21. The method ofclaim 8, wherein the routing module is further operable to enableend-to-end call routing.
 22. The method of claim 14, wherein a failureis a network interruption.
 23. The method of claim 14, wherein therouting module is further operable to enable end-to-end call routing.